The present invention relates to protective headgear to be worn by the passengers of a moving vehicle to protect against injury to the head. More specifically, it relates to protective headgear for use by the passengers of commercial aircraft during an emergency landing.
There presently exists an extensive variety of protective helmets to be used by persons riding in vehicles or engaged in athletic events to provide protection against impacts to the head of the wearer. Typically, these structures include a rigid or semi-rigid outer shell of metal or hard plastic and a liner of cushioning material interposed between the head and the shell.
The shell acts to prevent penetrations and to distribute the force of a blow directed at any one position. The liner acts to absorb part of the energy from the blow to reduce the amount of force transmitted to the head.
In some of these helmets, the cushioning material comprises an inflatable member mounted inside the rigid helmet shell. For example, U.S. Pat. No. 3,668,704 (Conroy et al.) shows an inflatable helmet liner used for cushioning purposes.
Such hard shell helmets may be suitable for use when numerous impacts are expected, such as when playing American football, or when the risk of accident is relatively high, as when riding a motorcycle. But, hard shell helmets have many disadvantages.
Most specifically, hard shell helmets are expensive and uncomfortable. They are bulky, heavy and difficult to store. For the foregoing reasons, such protective headgear is not used in many circumstances where head protection would be beneficial.
For example, the passengers and crew of nonmilitary aircraft do not typically wear protective headgear. This leaves the passengers vulnerable to head injury, particularly when a plane is forced to make an emergency landing under adverse conditions.
Vulnerability is particularly acute for certain passengers. Small children, for example, frequently ride on the laps of adult passengers. Because such children are not secured by seat belt restraints, they may be thrown about the airplane cabin during a sudden deceleration.
Even if wearing seatbelts, some juvenile and elderly passengers are unable to assume the head-between-legs emergency position recommended during emergency landings. Such a passenger is particularly susceptible to having his upper body thrown forward so that his head strikes the immediately forward seat back or bulkhead.
The frequency of emergency landings is low, so it is not reasonable to expect passengers of commercial airlines to wear helmets during flight. Nor is there justification for devoting storage space in an aircraft cabin for the number of bulky hard shell helmets needed to supply all passengers during an emergency landing. As a result, passengers are not provided with protective headgear, even during emergency landings.
Previously it has been unknown to construct protective headgear without a hard shell member. Possibly this is because suitable structures have not been devised for soft headpieces or because it was felt that a soft headpiece could provide little penetration protection.